Removable rear connector for a circular electrical plug

ABSTRACT

A connector composed of two hinged subassemblies ( 26, 28 ) that enable a removable rear connector to be fitted onto a plug ( 10 ) whether or not fitted with its wiring. Subassembly ( 26 ) comprises a collar formed of at least two sections ( 36   a,    36   b ) capable of being placed behind the plug ( 10 ). Subassembly ( 28 ) forms a ring formed of at least two sections ( 56   a,    56   b ) designed simultaneously to encircle the rear of the plug ( 10 ) and the collar. The ring operates in conjunction with the connector by means of threads ( 20, 60 ) and with the collar by means of a assembly consisting of a throat ( 62 ) and a ring-shaped ridge ( 54 ). The subassembly ( 26 ) is also prevented from rotating relative to plug ( 10 ).

FIELD OF THE INVENTION

The present invention relates to a rear connector designed to be fittedto the wiring side of a plug in order to fit said plug with an accessorythat serves, for example, to retain the cables and/or ensureleaktightness.

Throughout the present text the terms “rear” and “forward” assume thatthe rear of the plug is the side to which the cables are connected.

The removable rear connector of the invention may be used on any plugprovided with a threaded rear section. Cylindrical multi-conductorplugs, normally known as “circular plugs”, come into this category. Theplug of the invention may, however, be used on other types of plug suchas fiber optic connectors, hybrid connectors, etc.

BACKGROUND ART

Most electrical plugs of the prior art are provided with a threaded rearsection that enables a removable rear connector to be fitted to them.This connector, which constitutes an accessory for the plug, is oftenreferred to as a cable clamp since its main function is usually toretain cables in a desired position in the immediate proximity of theconnector.

Rear connectors of the prior art comprise a ring that constitutes a nutdesigned to be screwed onto the threaded rear section of the plug. Bymeans of one or more arms, this ring includes a system for retaining thecables composed, for example, of two half-flanges capable of pressingagainst one another by means of a screw. The arms connecting the ring tothe cable retaining system are shaped to hold the cables at the requiredangle. The cables may therefore be held in the axis of the plug or at anangle relative to this axis, for example 45° or 90°.

Irrespective of their shape, all the rear connectors of the prior artcomprise a ring constructed as a single part. Consequently, these typesof connector must be threaded onto the cables before the ends of thecables are connected to the plug. Failure to do this means that theoperator must disconnect all the cables from the plug and then reconnectthem including the connector. In addition to the time wasted carryingout these operations, the chances of connecting cables wrongly aregreatly increased.

Similarly, any maintenance operation to replace the connector or partthereof also involves disconnecting and reconnecting all the cables oncereplacement is complete. The drawbacks of this type of operation are thesame as when an operator has forgotten install the rear connector beforeconnecting the cables to the plug.

DISCLOSURE OF THE INVENTION

The subject-matter of the invention is thus a removable rear connectorwhose original design enables it to fitted to a plug to which the cableshave already been connected, or removed from the plug without the needto disconnect the cables.

According to the invention this is achieved by using a removable rearconnector for a plug that includes a threaded rear section characterizedin that it comprises:

a first hinged subassembly comprising at least two arc-shaped collarsections capable of forming a collar and having a stepped outer surface;

a second, ring-shaped, hinged subassembly formed by at least twoarc-shaped ring sections including a forward threaded section and a rearstepped section that fit the rear threaded section of the connector andthe stepped outer surface of the collar respectively.

This type of rear connected may easily be fitted onto or removed from aplug irrespective of whether the cables have already been connected,thereby overcoming all the problems of connectors of the prior art. Theconnector is fitted by positioning the first hinged assembly so that thetwo arc-shaped sections of the collar close over the bundle of cablesimmediately behind the rear threaded section of the connector. The rearthreaded section and the collar formed by the first hinged section arethus simultaneously encircled by closing the second hinged subassemblyaround them.

In a preferred embodiment of the invention the collar formed by thefirst hinged subassembly has a forward surface provided withanti-rotation means capable of operating in conjunction withcomplementary means formed on a rear surface of the connector. Theseanti-rotation means may consist of a toothed wheel formed on the forwardsurface of the collar.

In this embodiment of the invention the rear stepped section of theinner surface of the second hinged subassembly has a ring-shaped throatthat operates in conjunction with a ring-shaped ridge formed on theouter surface of the collar.

The second hinged subassembly is preferably composed of two hingedsemicircular ring sections capable of being connected at their oppositeends by a removable component such as a screw fitted parallel to theaxes of the said sections of the ring. This arrangement facilitatesfitting and removal, particular where several plugs are used side byside on the same panel.

Moreover, the first hinged subassembly advantageously comprises twosemicircular collar sections that are fastened firmly to the first endsof two arms and a half-flange on which the opposite end of at least oneof the two arms is hinged. Depending on the configuration chosen, thetwo arms may be hinged on the half-flange, or only one of the arms maybe hinged on the half-flange, the other being fastened firmly to it.

Cable clamping means such as a second half-flange are then fitted ontothe half-flange of the first hinged subassembly using removablefastening means.

To prevent any relative movement between the sections of the arc-shapedcollar of the first hinged assembly, the ends of these sections of thecollar preferably have complementary shapes so that they can fit oneinto the other.

BRIEF DESCRIPTION OF THE DRAWINGS

A preferred but non-limitative example of the invention will now bedescribed with reference to the attached drawings wherein:

FIG. 1 is a perspective view showing the two hinged subassemblies in theopen position, hinged around the removable rear connector of theinvention, together with a wired plug that may be fitted with theconnector; and

FIG. 2 is a perspective view similar to FIG. 1 showing the final stagesof fitting the connector to the plug.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT

In FIGS. 1 and 2 the number 10 is used to refer to generally a plug onwhich a removable rear connector of the invention can be fitted. As hasalready been pointed out, the removable rear connector of the inventionmay be used on various types of plug such that the plug 10 shown in thefigures only constitutes an example that should not be consideredlimitative of the possible uses of the connector of the invention.

In the version shown, connector 10 is a circular multi-cable plugdesigned to be mounted on a panel by screws (not shown) that passthrough holes 12 in plate 14. In this example plug 10 is a fixedconnector comprising cylindrical cavities whose openings are located onthe forward surface of the plug and designed to receive male contacts17.

Using principles known in the art, a removable plug comprising femalecontacts may also be directly coupled to it.

Behind plate 14 the plug 10 constitutes a cylindrical barrel 18 machinedwith a rear threaded section 20. Behind this rear threaded section 20cylindrical barrel 18 presents a rear surface in which there is at leastone triangular-shaped tooth 22. In a strictly non-limitative example,three teeth 22 may be provided on the rear surface of cylindrical barrel18, said teeth being regularly placed around the axis of plug 10.

A bundle of cables 24 is connected to plug 10. More precisely, each ofcables 24 is electrically connected to a male contact 17 that is theninserted into one of the cylindrical cavities 16 of plug 10 that extendfrom the rear to the front of the plug and whose openings are located onthe forward surface.

FIGS. 1 and 2 also show the main components of a removable rearconnector of the invention capable of being fitted to plug 10 or removedtherefrom without any of the cables 24 being disconnected from plug 10.

The removable rear connector of the invention comprises a first hingedsubassembly numbered 26 in the figures and a second, ring-shaped hingedsubassembly numbered 28. A detailed description of each of these twosubassemblies will now be given.

First hinged subassembly 26 is composed of three parts 30 a, 30 b and 32and each of parts 30 a and 30 b is mounted on part 32 by means of pins34 a, 34 b.

More precisely, each of parts 30 a and 30 b comprises a semicircularcollar 36 a, 36 b and an arm 38 a, 38 b, a first end of which is rigidlyfastened to its corresponding semicircular collar section. As can beseen from the figures, arms 38 a and 38 b and semicircular collarsections 36 a and 36 b may be constructed in a single piece. In theversion shown, arms 38 a and 38 b are more or less straight, connectedto the middle of semicircular collar sections 36 a and 36 b and lyingparallel to the axis of the corresponding section of the collar.

The third component 32 of the first hinged subassembly 26 is ahalf-flange on the ends of which parts 30 a and 30 b hinge. Moreprecisely, parts 30 a and 30 b are hinged on half-flange 32 by the endsof arms 38 a and 38 b opposite to those bearing semicircular collarsections 36 a and 36 b. Pins 34 a and 34 b are fitted parallel to oneanother at right angles to the axes of semicircular collar sections 36 aand 36 b.

The arrangement described above allows the first hinged subassembly 26to be either in an open position, as seen in FIG. 1, in which parts 30 aand 30 b are moved on pins 34 a and 34 b so that they are distant fromone another, or in a closed position, as seen in FIG. 2, in which parts30 a and 30 b are pressed together by the ends of semicircular collarsections 36 a and 36 b.

When first hinged subassembly 26 is in the open position, it may be putinto position or separated from plug 10 and its bundle of cables 24 asshown in FIG. 1. In contrast, when first hinged subassembly 26 is in theclosed position, the semicircular collar sections 36 a and 36 b form acollar that completely encircles bundle of cables 24 behind the rearsurface of cylindrical barrel 18 of plug 10.

In order to prevent any relative movement between the ends of the twosemicircular collar sections 36 a and 36 b when first hinged subassembly26 is in the closed position, the facing tips of these collar sectionsare constructed with matching shapes to fit into one another. Therespective ends of section 36 a are fitted with a projection 48 a and arecess 50 a while the corresponding ends of section 36 b are fitted witha recess (not visible in the figures) and a projection 48 b.

When first hinged subassembly 26 is in the closed position shown in FIG.2, the forward surface of the collar formed by the two semicircularcollar sections 36 a and 36 b presents anti-rotation means composed of atoothed wheel 52. More precisely, this toothed wheel 52 is formed oftriangular teeth that fit teeth 22 that project from the rear surface ofcylindrical barrel 18 of plug 10. These triangular teeth are machined onthe forward surface of each of semicircular collar sections 36 a and 36b.

The anti-rotation means formed by toothed wheel 52 thus operate inconjunction with the complementary means formed by teeth 22 to preventfirst hinged subassembly 26 rotating relative to plug 10 when said firstsubassembly is in the closed position and held against the rear surfaceof cylindrical barrel 18 by second hinged subassembly 28 as shown inFIG. 2.

When first hinged subassembly 26 is in the closed position shown in FIG.2, the outer surface of the collar formed by semicircular collarsections 36 a and 36 b forms a ring-shaped ridge 54. Said ring-shapedridge 54 gives the outer surface of the collar a stepped shape which, aswill be seen below, is used to form a translation connection betweensecond hinged subassembly 28 and first hinged subassembly 26 whileallowing them to rotate relative to one another while in the closedposition. Ring-shaped ridge 54 is formed of two sections machinedrespectively in each of the two semicircular collar sections 36 a and 36b.

Second ring-shaped hinged subassembly 28 will now be described in detailwith reference to the figures.

In the version shown, second hinged subassembly 28 is composed of twosemicircular ring sections 56 a and 56 b that are hinged at one end ofeach section by means of a hinge pin 58 that is parallel to the axes ofeach of the two sections. This arrangement allows second hingedsubassembly 28 to be either in an open position, as seen in the figures,enabling it to be fitted or removed, or in a closed position (not shown)in which the second hinged subassembly 28 forms a ring.

When in the closed position second hinged subassembly 28 encircles andstraddles the rear of plug 10 and the front of first subassembly 26.More precisely, second hinged subassembly 28 encircles both the rearthreaded section 20 formed on the cylindrical barrel 18 of plug 10 andthe stepped outer surface 54 of the collar formed by the twosemicircular collar sections 36 a and 36 b of the first hingedsubassembly 26.

In order to allow second ring-shaped hinged subassembly 28 to operate inconjunction with threaded rear section 20 and the stepped outer surface54 respectively, the inner surface of said second subassembly isprovided with a threaded forward section 60 and a stepped rear sectioncomprising an annular throat 62 when in the closed position. Thethreaded forward section 60 and the annular throat 62 are machinedrespectively in each of the two semicircular collar sections 56 a and 56b, as shown particularly in FIG. 1. More precisely, threaded forwardsection 60 matches the rear threaded section 20 of the connector and thestepped rear section 62 matches the stepped outer surface 54 of thecollar formed by the first hinged subassembly 26 when in the closedposition.

The arrangement described above means that when second ring-shapedhinged subassembly 28 is closed and encircles both the rear of plug 10and the forward section of first hinged subassembly 26, threaded forwardsection 60 and rear threaded section 20 fit into one another and annularthroat 62 fits over ring-shaped ridge 54. It is thus possible to rotatesecond hinged subassembly 28 around the axis of the connector in orderto screw it onto, or unscrew it from said second subassembly withoutrotating first hinged subassembly 26. The way the annular throat 62 andthe ring-shaped ridge 54 fit together means that rotation relative tothe two subassemblies is possible. The way these components fit togetherforms a translation connection between the two subassemblies that isparallel to the axis of the connector. Consequently, when in the closedposition the second hinged subassembly 28 is screwed onto the rearthreaded section 20, the toothed ring 52 fits onto teeth 22 and firsthinged subassembly 26 is fastened to plug 10.

In order to facilitate screwing and unscrewing of second hingedsubassembly 28 in the closed position, the outer surface of saidsubassembly is advantageous knurled or provided with flattened areas.

As can be seen in FIGS. 1 and 2, the sections of the opposite ends ofthe two semicircular ring sections 56 a and 56 b to hinge pin 58 areprovided with a removable component to connect them such as a screw 64.This screw 64 lies preferably parallel to the axes of semicircular ringsections 56 a and 56 b, i.e. parallel to the axis of the connector whensecond hinged subassembly 28 is in the closed position and fitted aroundthe rear end of the connector and the forward end of first hingedsubassembly 26. This characteristic makes it possible to assemble anddismantle second hinged subassembly 28 even when plug 10 is used in alocation with little free space, particularly close to other plugs.

In the version shown particularly in FIG. 2, removable half-flange 32supports cable clamping means comprising, in this example, a secondhalf-flange 66. Said second half-flange 66 may be fitted to half-flange32 by removable fastening means comprising, in this example, two screws68. Screws 68 pass through holes machined in the ends of the secondhalf-flange 66 and screw into threads in the pins 34 a and 34 b used tohinge parts 30 a and 30 b to half-flange 32.

Each hinged subassembly 26 and 28 is assembled in the factory. For thispurpose pins 34 a and 34 b and hinge pin 58 advantageously consist oftubular rivets.

In order to install the removable rear connector of the invention, thefirst hinged subassembly 26 is fitted first. This is done by placing thesaid first hinged subassembly in the open position as shown in FIG. 1 sothat the half-flange 32 is pressing against the bundle of cables 24 andthe two semicircular collar sections 36 a and 36 b are located behindthe cylindrical barrel 18 of plug 10. The first hinged subassembly 26 isthen brought into the closed position shown in FIG. 2 so that the collarformed by the two semicircular collar sections 36 a and 36 b encirclesthe bundle of cables 24 immediately behind cylindrical barrel 18.

The second hinged subassembly 28 is then fitted by presenting it in theopen position as shown in FIG. 1 and fitting annular throat 62 andthreaded forward section 60 of one of the two semicircular ring sections56 a and 56 b respectively on the ring-shaped ridge 54 and in the rearthreaded section 20 as shown in FIG. 2.

The second hinged subassembly 28 is then closed by shutting the secondsemicircular ring section so that it completely encircles the rearthreaded section 20 of the connector and the ring-shaped ridge 54 offirst hinged subassembly 26. The second hinged subassembly 28 is lockedin this closed position by means of screw 64.

Assembly of the connector is completed by screwing the ring formed bythe second hinged subassembly 28 onto the rear threaded section 20 ofplug 10 until the toothed ring 52 fits onto closely onto teeth 22.

When the removable rear connector is used to retain the bundle of cables24 as in the example described above, the second half-flange 66 isfastened to the first half-flange by screws 68. The bundle of cables 24is then clamped between the two half-flanges 32 and 66.

If it is necessary to replace all or part of the removable rearconnector for maintenance purposes, it can be removed by performing theabove operations in reverse order, again without disconnecting thebundle of cables 24.

As has already been pointed out several times, the invention is notlimited to the version described with reference to FIGS. 1 and 2.

For example, the removable rear connector of the invention may serve adifferent function from that described, such as ensuring leaktightness.The components ensuring leaktightness are supported by the first hingedsubassembly in the same way as the components used to support the bundleof cables in the example described.

Moreover, where the removable rear connector is used to clamp the bundleof cables, this function may be fulfilled by means having differentforms from those described. For example, cable clamping may be ensuredby cable bands, heat-shrunk sleeves, etc. The relative angle between thecable clamping means and the axis of the plug may be different from thecoaxial orientation described above. For example, the cables may be heldat 45° or 90° to the axis of the plug by making arms 38 a and 38 b moreelbowed.

Finally, the various means described, particularly those designed toprevent rotation of the first hinged subassembly relative to theconnector and to ensure the rotating connection between the two hingedsubassemblies may be replaced by any other equivalent means. Similarlythe shapes of the two subassemblies, particularly as concerns the numberof arc-shaped sections or parts comprising them may be modified withoutexceeding the scope of the invention. For example, instead of both beinghinged on half-flange 32, one of the two arms 38 a, 38 b may be rigidlyfastened to it; this would reduce costs by eliminating a hingemechanism.

What is claimed is:
 1. Removable rear connector for a plug including arear threaded section, said connector comprising: a first hingedsubassembly including at least two semicircular collar sections capableof forming a collar having a stepped outer surface; a second ring-shapedhinged subassembly formed by at least two semicircular ring sections andhaving an inner surface that includes a threaded forward section and astepped rear section that respectively match the rear threaded sectionof the plug and the stepped outer surface of the collar.
 2. Connector ofclaim 1, wherein the collar formed by the first hinged subassembly has aforward surface fitted with anti-rotation means capable of operating inconjunction with complementary means formed on a rear surface of a plug.3. Connector of claim 2, wherein the anti-rotation means comprise atoothed wheel formed on the forward surface of the collar.
 4. Connectorof claim 1, wherein the rear stepped section of the inner surface of thesecond hinged subassembly has an annular throat capable of operating inconjunction with a ring-shaped ridge formed on the surface of thecollar.
 5. Connector of claim 1, wherein the second hinged subassemblyis formed by two semicircular ring sections each having a respectiveaxis, the ring sections being hinged at one end of each section andcapable of being connected at their other ends by a removable componentthat is parallel to the axis of each of the two sections.
 6. Connectorof claim 1, wherein the first hinged subassembly comprises twosemicircular collar sections that are fastened rigidly to first ends oftwo arms and a half-flange to which the other end of at least one ofsaid two arms is hinged.
 7. Connector of claim 6, wherein the two armsare hinged on the half-flange.
 8. Connector of claim 6, wherecable-clamping means are fitted to the half-flange by removablefastening means.
 9. Connector of claim 8, wherein the cable clampingmeans comprise a second half-flange.
 10. Connector of claim 1, whereinthe semicircular collar sections of the first hinged subassembly haveends whose matching shapes make them capable of fitting one another.